In theology, a monad is part of a theory of God pertaining to the unity of the deity with the natural world.
In ancient philosophy, a monad was a hypothesized unit of matter that was a precursor the the concept of the atom.
In mathematics, monads refer to a type of "functor" used in Category Theory.
The concept of monads also shows up in computer science.
It was thus, with some puzzlement, that Natalie and I contemplated a sign advertising "frozlemonad". What sort of monad is a frozle monad? It sounds like something that the Frobozz Applied Theology Company might have been working on.
Eventually we surmized that the sign was actually advertising frozen lemonade.